diff --git a/.github/workflows/rails-main-branch-test.yml b/.github/workflows/rails-main-branch-test.yml
new file mode 100644
index 0000000..a15903b
--- /dev/null
+++ b/.github/workflows/rails-main-branch-test.yml
@@ -0,0 +1,18 @@
+---
+name: Tests on the "main" branch of Rails
+
+on:
+  schedule:
+    - cron: '15 8 * * MON'
+  workflow_dispatch:
+
+jobs:
+  test:
+    name: ActiveRecord main / Ruby 3.3
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - run: docker-compose run test
+        env:
+          RUBY_VERSION: "3.3"
+          AR_VERSION: "main"
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 2b2f07e..64dc925 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -20,7 +20,7 @@ jobs:
         include:
           - {activerecord-version: "5.2", ruby-version: "2.7"}
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - run: docker-compose run test
         env:
           RUBY_VERSION: ${{ matrix.ruby-version }}
diff --git a/gemfiles/main.gemfile b/gemfiles/main.gemfile
new file mode 100644
index 0000000..caac2b1
--- /dev/null
+++ b/gemfiles/main.gemfile
@@ -0,0 +1,11 @@
+source "https://rubygems.org"
+
+gemspec path: ".."
+
+gem "activesupport", github: "rails/rails"
+gem "activemodel", github: "rails/rails"
+gem "activerecord", github: "rails/rails"
+gem "sqlite3", ">= 1.4"
+gem "mysql2", "~> 0.5"
+gem "pg", "~> 1.1"
+gem "trilogy", "~> 2.7"
diff --git a/ulid-rails.gemspec b/ulid-rails.gemspec
index 1590715..9ac3549 100644
--- a/ulid-rails.gemspec
+++ b/ulid-rails.gemspec
@@ -47,5 +47,5 @@ Gem::Specification.new do |spec|
   spec.add_development_dependency "rake"
   spec.add_development_dependency "minitest", "~> 5.0"
   spec.add_development_dependency "rubocop-minitest", "0.34.5"
-  spec.add_development_dependency "standard", "~> 1.34.0"
+  spec.add_development_dependency "standard", ">= 1.35.1"
 end